OF THE ATMOSPHERIC TEMPERATURE. 



305 



Savannah, Ga. . 

 Fort Brooke, Fla 

 Cincinnati, Ohio 



Fort Snelling, Minn. 

 Muscatine, Iowa 

 St. Louis, Mo. . 

 Ft. Leavenworth, Kan. 



Fort Gibson, Indian 

 Territory . 



Fort Jesup, La. . 

 San Francisco, Gal. 



{Savannah .... 

 Augusta Arsenal . 

 Augusta .... 

 Oglethorpe Barracks 



Fort Brooke . 



I Cincinnati 



Marietta . . . 



College Hill . . 

 (^ Portsmouth 



I Fort Snelling . 

 [ St. Paul . . . 



f Muscatine . 

 1 Fort Madison 



f St. Louis . 



(. JeiTerson Barracks 



Fort Leavenworth 

 Leavenworth City 



j Fort Gibson . 

 i Fort Towson . 

 1^ Fort Washita . 



Fort Jesup 



Alcatraz Island 

 Angel Island . 

 Fort Point 

 Presidio 

 San Francisco 



25 years. 

 22 " 



6 " 

 12 " 



27 years. 



45 3'ears. 



46 " 



47 " 

 12 " 



42 years. 

 8 " 



26 years. 



22 " 



35 years. 

 3~ 



40 years. 

 5 " 



29 years. 

 16 " 

 15 " 



23 years. 



7 years. 

 3 " 



Constant Reduction +2°. 3 

 +2.7 

 " — °-9 



Constant Reduction -f-^"-! 

 + 2.3 

 " " — 0.1 



Constant Reduction -|-i°.9 

 Constant Reduction — 3°. 4 

 Constant Reduction — o°.i 

 Constant Reduction -|-i°.6 



Constant Reduction — [°.2 

 —1.9 



Constant Reduction — i°.o 

 +0.9 

 + 1.9 



On the whole the constant reduction deduced by a rigorous method and applied 

 to each separate series to refer to the central station, answered well enough, yet 

 there were indications, when the several series were thus brought side hy side, of 

 deviations from constant reduction for some consecutive years, which imperfections 

 may have been produced by a change of thermometer, a change in the location of 

 the instrument, or a change of observing hours ; in the latter case, it would indicate 

 an imperfect correction for daily variation. 



39 June, 1875. 



